Linux firewalld Rules

 Open all incoming connections on 5003/tcp port . Zone should be public

[root@master ~]# systemctl status firewalld

● firewalld.service - firewalld - dynamic firewall daemon

   Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)

   Active: active (running) since Sat 2021-02-06 23:02:29 EST; 2min 25s ago

     Docs: man:firewalld(1)

 Main PID: 32724 (firewalld)

    Tasks: 2 (limit: 11343)

   Memory: 23.9M

   CGroup: /system.slice/firewalld.service

           └─32724 /usr/libexec/platform-python -s /usr/sbin/firewalld --nofork --nopid

Feb 06 23:02:28 master systemd[1]: Stopped firewalld - dynamic firewall daemon.

Feb 06 23:02:28 master systemd[1]: Starting firewalld - dynamic firewall daemon...

Feb 06 23:02:29 master systemd[1]: Started firewalld - dynamic firewall daemon.

[root@master ~]# firewall-cmd --zone=public --list-all

public (active)

  target: default

  icmp-block-inversion: no

  interfaces: enp0s3

  sources:

  services: cockpit dhcpv6-client ssh

  ports:

  protocols:

  masquerade: no

  forward-ports:

  source-ports:

  icmp-blocks:

  rich rules:

[root@master ~]# firewall-cmd --permanent --zone=public --add-port=5003/tcp

success

[root@master ~]# firewall-cmd --reload

success

[root@master ~]# systemctl restart firewalld

[root@master ~]# firewall-cmd --zone=public --list-ports

5003/tcp

[root@master ~]# firewall-cmd --zone=public --list-all

public (active)

  target: default

  icmp-block-inversion: no

  interfaces: enp0s3

  sources:

  services: cockpit dhcpv6-client ssh

  ports: 5003/tcp

  protocols:

  masquerade: no

  forward-ports:

  source-ports:

  icmp-blocks:

  rich rules: